Marble-loving clematis with an Italian flat-leaf

I'm very familiar with the local clematis, although when I was working with Neville Walsh on the Flora of Victoria (1990), there were only three native species (one with two varieties). Now, there are five species.

I'm also familiar with the colourful exotic hybrids grown in gardens. All of them, as the Greek-derived genus name Clematis suggests, are climbers. 

This particular species, found in a local front garden, was new to me, and at first I was struggling to place it. The flowers were typical of its family, Ranunculaceae, but it didn't quite look 'creepy' enough for a clematis.

It's Clematis marmoraria or perhaps a cultivar/hybrid, such as Clematis petriei x marmoraria 'Perfection'. If it's the species, it carries the common name of North-west Nelson Marble Clematis, and it comes from, north-west Nelson - on the northern tip of South Island, New Zealand. It grows there on a single mountain peak, in the crevices of naturally occurring marble, which is why it's called marmoraria ('of marble'). 

Clematis marmoraria is an alpine or subalpine species, and although locally common, restricted in extent so considered rare. As you'd expect from that kind of habitat - the top of mountains - it doesn't ramble or climb wantingly. In this garden, so far, I'd describe its habit as clumping. The New Zealand Plant Conservation Network call it 'tufted suckering shrublet', which sounds a bit harsh. 

It is, I learn, the smallest Clematis in the world. I was also delighted to read that at first glance it might be mistaken for a Ranunculus or Anemone, which is pretty much what I did. The similar looking petals and sepals (the latter often green but here just looking like petals) and the feathery attachments to the seeds (which I didn't see) give the game away.

There are ten species of Clematis in New Zealand, as with most (all?) species in this genus the flowers male or female and on separate plants. The plants I photographed were male.

 

The foliage looks like celery, or perhaps a grevillea, popping up from slow growing underground stems (stolons).  Like parsley, the degree of leaf division varies among plants and could perhaps be selected by breeders. This one I'd describe as typical, or a little finer than, Italian flat-leaf.

Nothing much like what I'm used to for a Clematis, but it's always fascinating to see how a group of plants can evolve and adapt into unusual and unexpected forms.